165999853 has 4 divisors (see below), whose sum is σ = 166358848. Its totient is φ = 165640860.

The previous prime is 165999851. The next prime is 165999859. The reversal of 165999853 is 358999561.

It is a semiprime because it is the product of two primes, and also a Blum integer, because the two primes are equal to 3 mod 4.

It is a cyclic number.

It is not a de Polignac number, because 165999853 - 2¹ = 165999851 is a prime.

It is a Duffinian number.

It is a junction number, because it is equal to n+sod(n) for n = 165999794 and 165999803.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (165999851) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (17) of ones.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 178803 + ... + 179728.

It is an arithmetic number, because the mean of its divisors is an integer number (41589712).

Almost surely, 2^165999853 is an apocalyptic number.

It is an amenable number.

165999853 is a deficient number, since it is larger than the sum of its proper divisors (358995).

165999853 is an equidigital number, since it uses as much as digits as its factorization.

165999853 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 358994.

The product of its digits is 2624400, while the sum is 55.

The square root of 165999853 is about 12884.0930220175. The cubic root of 165999853 is about 549.5863037821.

The spelling of 165999853 in words is "one hundred sixty-five million, nine hundred ninety-nine thousand, eight hundred fifty-three".